1. Field of the Invention
The present invention relates to a detecting device, and, more particularly to a detecting device adapted to be capable of acquiring information on a slip necessary for stable gripping, skillful manipulation, and the like of an object by a robot hand.
2. Description of the Related Art
General tactile sensors in the past are classified into five types described below.
1. Examples of a sensor for contact (presence or absence of contact and confirmation of approach) include a limit switch, a pressure sensor, an optical sensor, a Hall element, and a capacitance sensor.
2. Examples of a sensor for a sense of pressure (pressure, a force, and a gripping force) include a semiconductor pressure sensor, a strain gauge, a motor potential sensor, and a spring displacement sensor.
3. Examples of a sensor for distributed tactile senses (a pressure distribution and a force distribution) include a pressure sensitive rubber+an electrode film, a pressure sensitive polymeric film+an electrode plate, an optical sensor+a rubber plate, and an integrated semiconductor pressure sensor.
4. Examples of a sensor for a sense of slip (relative displacement, slip oscillation, and a shearing force) include a roller or a ball+an encoder, an oscillation sensor, and a three-dimensional tactile sensor.
5. Examples of a sensor for a sense of force (a force and a moment) include a strain gauge+a structure, a strain block, an optical sensor+a spring, and a driving force sensor.
To perform complicated control such as stable gripping and skillful manipulation of an object by a robot hand, it is necessary to acquire gripping states such as a slip between the gripped object and fingers.
A tactile sensor for acquiring a gripping state among the tactile sensors described above, for example, JP-A-2006-47145 discloses a sensor having a multilayer structure in which a distributed pressure sensor and a flexible viscoelastic body are combined.
JP-A-2006-10407 discloses a detection sensor that includes a pressure sensitive element and a piezoelectric element and realizes detection of a sense of slip by performing a waveform analysis of the piezoelectric element and detection of a sense of force using the pressure sensitive element.
Moreover, JP-A-2004-226380 discloses a tactile sensor in which respective contact terminals of an element for detecting the pressure in the vertical direction and an element for detecting the pressure in a shearing direction are arranged not to overlap each other on a sensor surface and that obtains a sense of slip on the basis of a shearing force and a vertical force detected from the elements.